Field of the Invention
The present invention relates to the field of hot and cold water faucets having open and close mixing valve cartridges.
Description of Related Art
Valve cartridges are known in the art for faucet handles, whether for a single-handled faucet having a single mixing cartridge accepting flow from two water sources (hot and cold) or a two-handled faucet each having a cartridge to limit the amount of hot or cold flow through one of the faucets so as to adjust water temperature and flow volume exiting the faucet head. Such cartridges typically have a main housing and rotating valve pieces for controlling flow. A shaft or spindle extends through the center of the valve cartridge which is configured to interact with a faucet handle so as to turn or otherwise respond to allow water flow adjustment when the faucet handle interacting with the spindle is turned or moved depending on the faucet design.
The central spindle is typically subjected to force load in operation both in the axial direction as the user presses on the handle or in the lateral rotation direction as the spindle turns in the device and as the other parts act against the spindle both as a result of operating force to turn the spindle and frictional force as the spindle rubs against other parts. Various cartridge designs are known in the art to deal with this issue. See for example, U.S. Patent Publication No. 2008/0054210 A1 which incorporates a further part, a bushing, to account for use of more economical materials than traditional metal parts. Such force and friction wear can contribute to valve failure or leakage at the faucet area. Some of this issue is dealt with by using ceramic seals, however, such devices may require redesign to accommodate the ceramic seal. See, e.g. U.S. Pat. No. 6,202,695 (using an offset eccentric flow passage) and U.S. Reissue Pat. No. 35,545 (using a specialized frictional protective retainer for protecting the cartridge valve seal.
Varying designs are created to take account of these effects and/or to improve interaction with the faucet handle(s) while trying to maintain standardization in terms of flow rate and fitted parts.
There is still a need in the art to reduce friction, wear and failure in faucet handle valve cartridges, while providing adequate or enhanced flow through the cartridge device. There is further a need in the art for an adaptable design that works with increasingly creative modern faucet and faucet handle design features.